The purposes of this study are: (1) to compare the body composition, physical activity, physical function, and quality of life between patients with and without CKD after CABG; and (2) to analyze the relationships among body composition, physical activity, and physical function in this population. It is expected that patients after CABG with CKD have the worse body composition, physical function, and quality of life than patients after CABG without CKD; and patients with higher physical activity levels have the better body composition, physical function, and quality of life.